Conventionally, ultra-hard alloy tools are widely used as cutting tools. Hard films such as TiN or TiAlN are typically applied to these ultra-hard alloy tools for the purpose of increasing abrasion resistance.
Also, ultra-hard alloy tools coated with a diamond film using chemical vapor disposition as disclosed in, e.g., Patent Document 1 have recently been used for cutting hard carbon materials, Si-containing aluminum alloys, and other nonferrous high-hardness work materials.
Currently, however, indications have appeared in which the diamond film is destroyed or otherwise damaged during cutting, and a sufficient abrasion resistance is not obtained in relation to ultra-hard alloys and other work materials having a very high degree of hardness.